Baffle for mixing devices



Aug. 9, 1966 R. J. NOCERA 3 3 BAFFLE FOR MIXING DEVICES Filed April o. 1964 FIG. 2

, INVENTOR.

RAY J NOCERA vsyf ATTORNEY allel portions of the D is partally flattened to provide al generally oval-shaped configuration.

When the bafile has been completely fabricated, one or more continuous layers of glass or vitreous enamel are applied to the surface to provide a smooth, corrosion resistant surface.

The preferred embodment as illustrated in the drawings is a D-shaped configuration in which the parallel portous of the spaced members are flattened to form an oval-shaped section as shown by member 14a. However, since the avoidance of sharp corners is necessary to prevent the glassing diiculties discussed above, the edges should still remain rounded.

I have found a D-shaped configuration to be most ad- Vantageous, but in accordance with the basic objects of our invention, e.g. the achieving of maximum baffiing width and improved baffiing without sacrificing the structural strength of the glass coated baffle, it is not limited to a D-shaped configuration. Accordingly, the use of more than two spaced members joined at one end to a mounting member and at their other ends to each other is within the scope of my invention. Moreover, such joining may be directly or by means of a transverse mernber, as 'long as sharp angles and narrow edges are avoided.

In any mixing process an important factor that must be considered is power consumption. When baffles are absent or inadequate bafiling is provided, rotary motion or swirl is set up. Less power is consumed under these conditions than is consumed when vertical currents are present. Therefore, to measure the elfectiveness of a baflle, it is customary to observe its eifect upon the power Consumption. It is preferable to measure power consumption over an increasing range of power input. If suficent power is applied swirl, vortex, and air entrapment can be obtained with the best of bafiles. The more effective baflle will thus retard such effects at higher power inputs. In accord with the above, I have found that two D-baffles will absorb approximately 28% more horsepower than two finger baffles.

In addition to measurements of power input, the relative effectiveness of bafiles is commonly determined by visual observation of the agitation effects. The fiow pattern produced by two D-baffies exhibited a high velocity at the wall of the vessel, high turbulence behind the baffie and a powerful top-to-'bottom turnover. Vortex control was excellent and agitation effect approached that of a four sidewall baffie system.

Tests conducted with a 44 inch Pfaudler impeller in a 1000 .gallon tank of water using a H.P. variable speed motor and two baffles mounted as illustrated in the accompanying drawings are shown in the follcTwing table.

TABLE I Percent Net Input Net Iuput Increase H.P. for ILP. or in Power Bpm. 2 Finger 2 "D" Over 2 Bafilcs Balles Finger Bafles Additional tests were conducted with smaller vessels that substantiated the superior performance of the subject bafile.

Although I have not provided data detailing the dimensions of bafiles according to my invention, such information is readily accessable to those skilled in the art. Typical applications are governed by the rule-ofthumb wherein 4 equally spaced bales extending the full length of the vertical sides, each having a width /2 of the vessel diameter is considered standard. But such rules are arbitrary and generally the most efficient baffling for a given fluid is determined empirically.

Bafiles according to this -invention can be used as heai transfer sur-faces, and can be used on existing vessels without vessel re-design. The glass coating permits effective bafiling in highly Corrosive mediums wherein it i: not advisable to disturb the integrity of the tank lining` Although I have shown this bafile with impeller type agitation devices, it is not limited thereto and may be usec' with other devices such as turbines. The modification oi the bafile elements for the inclusion of the thermomete wells and the like may be done in accordance with prioi art practice.

The term glass coating as used herein includes -glass 01 ceramic coatings, whether amorphous or devitrfied.

Although the invention has been illustrated by a par ticular preferred embodiment, it is to be understood tha such disclosure is intended to be illustratve, not limit ing, and that various modifications that will become ap parent to those skilled in the art are within the scope o: this invention and the appended claims.

I claim:

1. In combination with a vessel having mixing means a baffle comprising,

(a) a mounting member adjustably mounted outsid said vessel and adapted for extending into said vessel (b) a plurality of rounded spaced members substan tially arallel intermediate their ends, joined to sai( mounting member at one end and to each other a their opposite ends, and extendig into the vessel, the portions of said baflle within the vessel being glas coated.

2. Apparatus according to claim 1 wherein said space members are in the same plane, the substantially paralle portions of said spaced members are oval shaped, am the major axes of said oval-shaped members are in th` said plane.

3. Apparatus according to claim 1 comprising tw spaced members joim'ng said mounting member and eac other to form a D-shaped member.

4. Apparatus according to claim 3 wherein said space` members are in the same plane, the substantially paralle portions of said spaced members are oval shaped, an the major aXes of said oval-shaped members are in th said plane.

References Cited by the Examiner UNITED STATES PATENTS 3,063,684 11/1962 Hayashi 259-10 POREIGN PATENTS 204,684 8/1959 Austria.

WALTER A. SCHEEL, Prima'y Examner.

R. W. JENKINS, Assistant Exam'ner. 

1. IN COMBINATION WITH A VESSEL HAVING MIXING MEANS, A BAFFLE COMPRISING, (A) A MOUNTING MEMBER ADJUSTABLY MOUNTED OUTSIDE SAID VESSEL AND ADAPTED FOR EXTENDING INTO SAID VESSEL, (B) A PLURALITY OF ROUNDED SPACED MEMBERS SUBSTANTIALLY PARALLEL INTERMEDIATE THEIR ENDS, JOINED TO SAID MOUNTING MEMBER AT ONE END AND TO EACH OTHER AT THEIR OPPOSITE ENDS, AND EXTENDING INTO THE VESSEL, 